Stencil printing machine



5 1940 .1. Kl-:ssEL

STENCIL .PRINTING MACHINE Filed lay 2, 1938 f5 Sheets-Shelf: 1

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3 Sheets-Sheet 2 Feb- 6, J KESSEL' STENCIL PRINTING MACHINE Filed May 2,1938 Feb. s, 1940. J. AKESSEL 2,189,001

STNCIL PRINTING MACHINE Filed lay 2, 1938 3 Sheets-Sheet 3 445 400 mavPatented Feb. s. i940I f 2,189,007

UNITED STATE-s PATENT oFEicE 2,189,007 s'rENcn. PmNTmG MACHINE JosefKessel, Krefeld, Germany Application May 2, 1938, Serial No. 205,479

In Germany September 10, 1936 13 Claims. (Cl. lol-123) Stencil printingmachines are known with in- Fig. 1l is a top plan view of the front endof termittently travelling printing supports and with a stencil, yarrangement for automatically lifting and loW- Fig. 12 is a sideelevation of Fig. l1, eringvthe stencils and for moving the doctors toFig. 13 shows the lay out of the machine for and fro. electric drive. 5

The invention has for its object to carry out The stencil printingmachine comprises subautomatically all operations lnecessary for thestantially a printing table covered with felt printing of webs and thelike. This object is and adapted to be heated from below, aroundattained according to the invention in that the which table an endlessband 2 of rubber, rublaterally unshiftable and unstretchable printberedfabric or the like circulates in the longitu- 10 ing support providedwith a heating device, a dinal direction of the table and is moved inlonheated pasting and Washing device is driven by gitudinal directiontowards a roll 3' by rolls 3 a suitable continuously running motor andconand 4 mounted on the short ends of the printtrolled by a gear and twoclutches at two difing table i- The 1011 3 is keyed on the drivingferent speeds Whose change over from rapid shaft 5 of the machine towhich the'rotary mo- 15 speed to creeping speed is` effected by a catchtions of a driving motor A are. transmittedl which clamps the supportand during the forthrough the intermediary of a gearing arrangewardtravel thereof successively disengages the ment B for full orsemi-automatic operation. A clutch for rapid speed, engages anddisengages pasting arrangement I is arranged adjacent the the clutch forcreeping speed and actuates a roll 4 for automatically applying pasteand above 20 fine adjusting device' whichindicates lthe regthe printingtable stencils 6 are arranged which ister position and releases thecatch for the rein conjunction with a doctor mechanism II serve turnmovement and engages in the drive of the for printing the Web 1 ofSmooth 01 Tough fiiili machine an auxiliary motor which imparts a orpaper or other material running off a ro1l.

half revolution to a toothed wheel'and a switch Below the printing tablei there is a washing ar- 25 disc connected -therewith and thus lowersthe rangement III through Whieh the lower Side of stencils on to theweb, and switches on another the band 2 passes to be automatically freedfrom auxiliary motor which actuates a doctor mechanpaste, printing inkor'the like adhering to its ism and again switches on the motor forraising surface. The printing table I, is composed of the stencils,which last mentioned motor eiects several plates adapted to be ttedtogether, sup- 30 the engagement of the rapid speed clutch and Ported bygirders 8 and closed at the sides, and the Aclamping of thel catch onthe printing supis closed from below like a box byl the lower side port,4 of the band. A heating arrangement 9 in this An embodiment of theinvention is illustrated table is constructed as an automatic hot air,

by way of example in the accompanying drawsteam or electric heatingarrangement,A or the 35 ings, in which: i like, or may be connected to acentral heating Fig. l is an elevation of the machine viewed System andS0 installed, .that the heating mefrom the gearing side. dium passes notonly through the printing table Fig. 2 shows the pasting arrangement ofthe but also through a pressure cylinder I0 for pressmachine in top planview, ing the web I to be printed against the pasted 40 Fig. 3 is a topplan view of the gear with nne printing support 2, the Washingarrangement III adjustment device, y and the drying device IV for the.printed web. Fig. 4 is a' vertical central section through The heatradiated by the printing table and the pasting arrangement, the pressurecylinder I0 is utilized for pasting Fig. 5 shows in front elevation thegearing on the web 1. To enable the web to be nxed 45 and the raisingand lowering device for the on the printing Support 2 in stretchedcondition stencils, l as little paste as possible is applied on the sup-Fig. 6 is a top plan'view of the doctor mechport 2 in stripes Il by aribbed cylinder I2 (Fig. anism, 2). This cylinder I2, which is composedof parts Fig. 7 shows the doctor reversing mechanism which rest looselybetween the printing Support 50 in side elevation, 2 and a paste feedingroll dipping into the paste Fig. 8 is a top plan view of Fig. 7, box I3and connected by toothed gear wheels Fig. 9 shows the ne adjustmentdevice in with the roll l, is guided laterally only by adtop plan view,justable levers I5, and is rotated by friction by Fig. 10 is a sideelevation oi.' Fig. 9, the movement of the printing support and the 55roll I4. The ribs of the body I2 are preferably so narrow; and spaced sofar apart that the paste stripesll applied to the printing support 2 donot contact after being rolled out. In the pasting arrangement I asqueezing cylinder I6 is also arranged which is adjustable in itsbearings and prevents Athe roll I4 from taking up too much or too littlepaste. As paste, dextrine has for example been found suitable, as itbecomes glasshard when dried by heat, but rapidly re-dissolves in warmwater, so that it is possible to remove it without difflculty from theprinting support in the washing arrangement III. On the other hand therolled-on paste only penetrates slightly into the fabric and thus keepsthe fabric in a state perfectly capable of taking up ink.

Above the pasting arrangement I adjusting levers I1 and guide plates I8are arranged at the two sides of the band 2, the plates I8 having flapsI9 extending vertically downwards and bearing against the edges of theband, so that the band 2 is positively guided on to the printing tablein the correct position. The band 2 runs along the printing tablewithout clearance between two guide bars 20 fixed at the sides oftheprinting table, and from these bars 20 a resilient holding clown element2|, for example a thin sheet metal, rubber, reinforced fabric strip orthe like, extends across the printing support so that the latter isenclosed as in a groove. The two guide plates I9 exert a resilientpressure on the yieldable band also from above and facilitate itspassage on to the printing table by pushing the band inwards. Guiderollers or similar means might be employed instead of guide plates.` Theprinting support is preferably supported in the gap between the roll 4and the printing table I by a transverse support 22. The positivelateral guiding of the upper side of the band counteracts diagonal andlateral displacements thereof which may be caused by the band structure,heating and cooling, and so forth, so that the printing support 2circulates Wit-h its central longitudinal axis exactly in register withthe longitudinal axis of the printing table. A uniform running of theprinting support is also ensured in that the feed and guide rolls.3 and4 are interconnected by a stretchable driving chain 23 which runs overthe driving shaft 5 of the machine.

The iilm printing stencils 6 required for the printing are mounted on apair of rigidly interconnected vertically shiftable bars 24 arrangedparallel to the printing support 2, this pair of bars being guided withfrictional contact by guide rods 25 in one or more guides 26 mountedvertically on the printing table I, so that longitudinal and lateraldisplacementsof the pair of bars 24 cannot occur and consequently in thecase of multicolour printing the stencils are always accurately inregister the one above the other. The raising and lowering of thestencils takes place when the printing support 2 is at a standstill andis effected by a lever 21 which is constructed as a bell crank lever andactuated by hand. 'Ihe lever 21 is connected by a connecting rod 28 witha lever system 29 by whose movements the pair of bars 24 andconsequently the stencils 6 are moved up and down. A second rod 36connects the lever 21 with a crank disc 3l of the motor C, so that thestencils 6 can also be raised and owered by motive power. The stencils 6are iixed by front and rear riders 32 and 33, adapted to be clamped onthe two bars 24. The front riders 32 engage behind abutment bolts 34mounted on the longitudinal sides of the stencils and press the stencilsby clamping screws 36 with hand operable head against the front barserving at the same time as abutment bar for the pressure table `I.Thus, the front end of the stencil is unshiftably fixed in thelongitudinal and transverse direction of the printing table. In orderthat also the rear end of the stencil cannot shift laterally, the rearriders 33 are constructed as lateral stops between which the stencil isstretched. On one of the narrow sides of the stencils there is anabutment Vbolt 36, by means of which any turning of the stencil aroundthe vertical axis can be noticed and its lateral fitting is renderedpossible. The number .of stencils to be fixed depends upon the number ofcolours to be printed and may vary within limits as desired. In theexample described and illustrated two stencils are provided, eachstencil prints a separate color,

and the second stencil prints over the first. By employing stencilscorrectly cut according to color, a large range of shades can beproduced with only three or four stencils, and the length of theprinting table can be relatively short. A great number of stencils withwhich only one colour can be printed are necessary for producing amulticolour print and consequently require a machine of relatively longconstruction, in which case merely the printing table with printingsupport requires to be changed, whereas the two head endslof the machineremain unchanged. 'I'he machine may also be of a width, to allow theprinting of wide webs or single pieces such as table cloths, or the likein a single process.

The printing, which takes place whenl the printing support is at astandstill and the* stencils are lowered, is effected either by means ofthe automatically operating doctor mechanism II or by hand by moving'theprinting ink backwards and forwards on the stencils 6. In the case ofautomatic operation the printing ink is spread by means of a spreader ordoctor through the stencils on to the web 1 which is moved to and fro bya motor D independent from the mo.- tor C: In the case of handoperation, the doctors are moved to and fro by hand. The latter methodonly comes intoquestion, when stencils with coarse and ne patterns areused at the same time or when little ink is required at one portion of aprint section and a lot of ink at another portion. The heat radiated rbythe printing table exerts a favourable effect on the print- ,ingoperation in that the ink after being applied on to the web at the sametime gives up moisture, which deposits on the open portions of thestencils with a. gauze ground, whereby the printing ink is continuallymaintained in soft condition and the meshes in the pattern of thestencil are kept open. Thus, it is possible to print withoutinterruption, or to wash out the stencils only when the service isstopped for a relatively long time, for example, over night. After theprinting operation the stencils 6 are raised automatically by the lever21 or by hand, whereupon the printing operation is terminated. Theprinted web 1 then passes at the next feedinto the drying arrangement IVinto which it is drawn by means of a winding cylinder 38 on which an endstrip 39 connected with the beginning of the web 1 is i'lxed. TheWinding cylinder 38 is driven by a belt 40 or the like through theintermediary of the driving shaft 5 of the machine. A driving shaft notshown may be mounted in the bearings of the winding cylinder 38 insteadof this cylinder, and this shaft drives a mechanism by which the nishedmaterial is run out of the drying arrangement IV, to a folding andcollecting device.

While a length of web 1 equal to the length of a repeat is being pulledoff the printing support 2, the lower side of the band 2 moves throughthe washing arrangement III. This arrangement comprises a vessel 4l,through which a heating medium passes, rotary brushes 42 dlpping i ntothe water in the vessel, laterally shiftable stricklers 43 arrangedunder the printing support and counter pressure rollers 44 mounted abovethe printing support 2 and the stricklers 43, by which elements anypaste softened by the warm water while the printing support is standingstill, and also ink'smears, are washed and scraped off the support as itis moved on. The brushes 42 and stricklers 43 receivel their' drive,from a gear B through the intermediary of a chain drive or the like anda rod system 43a actuated by a grooved cam 43b on the end of the shaft5. The cleansed printing support 2 is stretched on its travel to thepasting arrangement I by a stretching roller 46 and dried by the heatradiated downwards from the printing table.

If the support 2 is fed at a low speed the output of the machine will betoo small, and if itis fed at a high speed the impetus will be too greatat the end of the feed to ensure accurate registering. Consequently theband must run at a high speed at the commencement of its feed and beslowed down so that it moves into its extreme end position at a creepingspee'd. l

The feed of the printing support 2 from one printing position to thenext may be produced by the motor A or by hand. The motorA is connectedwith the driving shaft 5 by the gear B which can be alternately engagedand disengaged by electric clutches E and F or by a hand-actuated clutchG. The clutches E and F serve to quickly and slowly move the printingsupport 2 in the case of electric drive, and the clutch G, which is onlyactuated when the clutches E and F are currentless, serves for the quickmovement and, in combination with a brake H, for the creeping movement,whereas a hand wheel J mounted on the countershaft 41 of the gear Bmakes it possible to move the printing support y 2 by hand.

The operation of the clutch G is conditional upon the raising andlowering of the stencils 6 and the doctoring of the printing ink beingcarried out by hand, and the motors C and D, and

`fixed point, and thus couples this pulleywith the counter shaft 41,this causing the feed of the printing support 2 at high speed throughthe intermediary of the wheels 53, 54, 55, 56 ofthe gear B, whichproduce a reductionof the speed oi. rotation of the motor shaft. Whenthe hand lever 5l is swung back, the clutch G is disengaged again and atthe same time the 4cheek brake I-I is.applied and the printing supportstopped. The cheek brake H is arranged in the gear wheel 56 forming acasing and mounted on the driving shaft 6, and is actuated by a cam 51controlled by a cam disc 58 arranged on the rear end of the controlshaft 50. The rotation of the counter shaft 5 can then be carried out byhand by the hand wheel J, in order to attain particularlyne adjustmentsof the printing support in its repeat` position.

Manual adjustments, which are necessary in the case of' semi-automaticservice, are carried out with the ald of a fine adjusting device K whichcomprises a magnifying indicating device, consisting for example of abipartite, unequal armed indicator 59, 60, whose short arm 69 iscillated through a small angle by the contact witha catch L adapted tobe clamped on the printing support 2. whereas the arm 60 connected withthe short arm 59 by intermeshing teeth, swings out against the action ofa spring through an angle many times greater than that of the deflectionof arm 56 until it strikes against an adjustable electric contact 6| orthe like by which the feed of the printing support is very accuratelylimited and optically or acoustically indicated or, in the case ofelectric drive, one

or several electric switches are actuated which y will be hereinafterdescribed.

The catch L, which has a clamping plate 63 adapted to be clamped on theprinting support 2 electromagnetically or by hand with the aid of aremovable lever 62, is pushed back by hand or mechanically up to a stop64 adjustably fitted in the initial position or to the beginning of therepeat when the printing support reaches its extreme end'position. Themechanical return of upon it is carried along until it encounters theshort lever arm 59 of the ne adjusting device K.' By turning the handwheel J the fine adjusting device allows the smallest movements of theprinting support to be read, so that it can vbe adjusted absolutely inregister below'the stencils 6 which are in the raised position.

When the printing support 2 has been vadjusted, the stencils 6 arelowered by means of the two armed lever 21, whereupon the printing inkis distributed on the web 1 mechanically or by hand through thestencils. After the printing ink has been stirred the stencils are againraised by means of the two armed lever 21.

In the case of electric drive the motors A, C and D become operative insuccession. The three motors are connected to a common supply main Mand, like the other driving means of the stencil printing machine, theycan be switched on and off alternately or partly simultaneously byswitches a, b, c, d, e, f, connected up in a low or high tension circuitN, and thus effect the uninterrupted drive of the machine. The clutch Gand brake I-I are disengaged during the electric drive and the lever 62of the catch L is removed, so that the catch can now be electricallyclamped on the printing support 2 and mechanically returned by the screwspindle 65. This screw spindle only lserves for the idle return of thecatch, but rotates continually. A belt 65a extends from the shaft 12 ofthe transmission gear 66 to a shaft 65h on which a Abevel wheel 65e ismounted which permanently meshes with catch L is effected bya screwspindle 65 which extends through the catch and Ais continually.

a bevel wheel 66d on the screw spindle. The electric clutches E and F inthe gear B and the electromagnets 61 and 69 in the catch L- now becomeoperative which have been switched in by the switches a-f of the plant.The clutches E and F effect successively the quick and slow rotation ofthe driving shaft 5 of the machine and consequently the quick orcreeping feed of the printing support 2. The counter shaft 41 carries asecond pulley 18 with the clutch E and a third pulley 1| with the clutchF. The pulley 10 is directly connected with the shaft of the motor A bya belt and the pulley 1| with the shaft 'l2 of the transmission gear 66alsov by a belt. Both pulleys 10 and 1| i'lrst run idle. When the clutchE is engaged, that is the pulley 18 is coupled with thel counter shaft41, the printing support 2 moves forward at high speed through theintermediary of the wheels 53, 54, 55, 56 of gear B. If the clutch F isengaged and the pulley 1| coupled with the counter shaft 41, the numberof revolutions of this counter shaft is reduced by the reduction gear 6Eso far, that the printing support is moved by the gear wheels 53, 54,55, 56 only at a creeping pace intoits extreme repeat position, which isdetermined by the iine adjusting device K, whereas in the case of handoperated driving shaft 5 the extreme repeat position of the printingsupport, as stated, is only indicated magnied by the deflection of theindicator 68 up to the electric contact 6|. At the same time when theprinting support 2 comes toa standstill, in the f plate 63 of the catchL is loosened and the pin 68 remaining permanently in the aperture ofthe hollow magnet 61 is caused to drop, and thus effects the return ofcatch L through the intermediary of the screw spindle 65. 'Ihe screwspindle has at one end an annular groove 13 into whichvthe pin 68 glideswhen the catch is in its initial position, and is held in this grooveuntil the magnet 61is reexerted. The annular groove 13 and the abutment64 allow the catch to pass into the initial position at the same height.During this time the motor C; which participates in the electriccontrols by means of a switch disc 14 connected with the crank disc 3|,effects the lowering of the stencils 6 by a half-revolution. A pinion 15on the shaft of the motor C transmits the rotations of the shaft to thecrank disc 3| constructed as a spur wheel and connected with the stencilholding bars 24 by the lever system 30, 21, 28, 29. The half revolutionof the crank disc 3| is automatically controlled by switches a-f of theplant and by the control disc 14 over which the motor C is automaticallyswitched out after the lowering of the stencils. The stencils beinglowered, the switched oi motor C effects through the switch disc 14 andswitches a/-f of the plant the switching in of the motor D, whichactuates the doctor device II for distributing the printing ink throughthe stencils on to the web 1. 'I'he doctor device II (see Figs. 1 and 6)consists of two endless pulling elements for example chains 11, drivenby a chain 11a through the intermediary of ashaft 11b (Fig. 6). 'I'hechains 11 carry a cam 18 and a bolt 19. 'I'his bolt 19 circulates withthe chains 11 about the axles of this driving wheel and moves a carriage88 to and fro, whereas the cam 18, in` circulating with the chains 11,feeds the control disc 8| through a part revolution. This control disc8| has contacts 82 arranged in star shape which are brought into contactwith a spring 83, thereby closing one of the switches a-f and stoppingthe motor D. 'I'he ends of a pull rope 84 are connectedv to the ends ofthe carriage 8|), so thatl thisrope constitutes an endless pullingmeans. This pull rope is guided over pulleys 81 in such a manner that itextends across the printing table at three j l points as a doublepulling rope, one of whose sides always runs in the direction in whichthe this pulling rope and is consequently moved to and fro across thetable in synchronism with the to and fro motion of the carriage. Thestencils 6, adjusted and xed according to register over the printingsupport by front and rear abutment means 32 and 33 lie between the outerguide bars 86 with guide or rope pulleys arranged on their ends. A thirdguide bar 88 is preferably provided between the stencils and alsocarries a guide pulley so that the Apullingv element extends from oneend of the carriage 80 and is guided several times across the printingtable between the end guide bars 86 before reaching the other end of thecarriage 88. The doctor holder 85 is carried at each end by a verticallyshiftable spring bolt 89 mounted in a carriage 98 (Figs. 7 and 8) andprovided with a roller 93 resting on a cam bar 9| slidable along the endguide bars 86, 88 between abutments 92. Each caml bar 9| has twoabutments 94, one at each end. As the doctor holder 85 moves to and fro,it shifts the cam bars 9| by means of the bolts 89 whose rollers 93 bearagainst the abutments 94 at the front end of the cam bars 9| in thedirection of movement. At the reversal of the doctor holder 85 the cam'bars 9| first remain stationary and the rollers 93 run along' the camrace thereof and vertically shift the spring bolts 89, before reachingthe abutments 94 at the actually inner end of the cam bars, whereuponthese cam bars are shifted to the abutment at the other end of the guidebars 86, 88 where, at the reversal of the doctor holder 85'.theoperation is repeated. The doctor holder 85 is carried by the bars 24and consequently ascends and descends with the stencils. The

doctor holder 85 consists of a bar Iwith longitu- 9|, to behind the heapof ink and push it before them in the opposite direction as the doctorholder continues its movement. 'I'he number of to and fro motions can beregulated by the switch discv 8| which switches oi the motorv D eitherthe first time the cam 18' contacts or only after it has contactedseveral times. The contacts 82 of the switch disc 8| may be eitheradjustable or unadjustable, or can be separately adjusted for each kindof movement. When the advancing cam 80 contacts with one of theabutments of the switch disc 8|, of which asl many are provided as thereare contacts 82, it moves the switch aisaoov to and fro movement of thedoctor holder.-

If two cams 18 are arranged on the catch chain spaced at a certaindistance, the motor D is stopped after a single to or fro motion. If,however, there is only one cam on the chain 11 and six or less contacts82 are provided on the switch disc 8|, in the case of twelve abutments,v

the contact spring 88 only comes into contact with a contact 82 afterthe cam 18 has circulated two or more times, so that the motor D is cutout only after the doctors have performed two or more reciprocatingmovements.

After sufficient doctoring or after the motor D is cut out, the motor Cis again connected in the circuit through the switch disc 14 andswitches c-f of the plant so that after the shaft of the motor hasperformed another half revolution lifts the stencils and at the sametime closes the circuit of the catch magnets 61, 69 and of clutch F. Thepin 68 is thus drawn into the hollow magnet, that ofthe catch L isunlocked, the clamping plate 63 is clamped on the printing support 2 andthe catch advanced by the printing support 2 which is fed at high-speedthrough the clutch E. Just in advance of the fine adjusting device K atravel stop 91 `is arranged with two contact levers 98 and 99, whichstop is laid down by the advancing catch L against the action of aspring |00, and through the intermediary of contacts |0| and |02,successively actuates two of the electric switches a-f by which thedisengagement of the clutch E and a moment later the engagement of theclutch F is effected. As soon as the printing support has arrived attheV end of the repeat feed, the catch L knocks over the lever 59 of thefine adjusting device K which swings the pointer 60 up to the contact6I, whereby throughv the intermediary cf three switches of the plant a-fthe circuit of the clutch F is opened and at the same time the circuitof the catch magnets 61, 69 and of the motor C is closed.

'Ihe electric drive of the machine takes place in the following manner:First the main switches |03l and |04 of the supply mains M and thesecondary circuit N are closed and the main driving motor A is switchedon by closing the circuit by a press button switch |05 or the like, thedriving shaft 5 being declutched. Current then flows through the wire|06 across the press button switch |05, a protecting device gseries'connected with the motor A and whose switch is closed andconducts the current through the return wire |01 to the mains M andthrough the wire |08 to the motor A and thence over the return wire I1back to the mains M. It is supposed that the catch L has turned over thelever 59 ofthe fine adjusting device K. Across the pointer 60 andcontact 6| of this device the switches e and f of the secondary circuitN are opened, the magnets 61 and 69 of the catch L and the creepingmotion clutch F are rendered currentless and at the same time the switchd is closed and the gear motor C is switched on and now effects thelowering of the stencils 6. When the circuit is closed by the pointer 60and the contact 6|, the current flows .along the following path: sourceof current |09, feed wire IIB, pointer 60, contact 6| of the iineadjusting device K, wire |29, switch f which isopened, return wire I II, switch e which is likewise opened, return wire III, switch d whichisclosed, return wire III to source of current |09.` The mains currentflows over the closed switch d along the followingpath: feed wire |06,closed switch d, wire II2, relay i, whose switch is closed over thereturn wire |01, wire |80, gear motor C, return wire |01 to the. mainsM.Whilst the gear motor C is running the spur wheel 8| performs a halfrevolution, whereupon two friction contacts |I3, V| I4 arranged on theperiphery of the switch disc 14 connected` with the spur wheel 3| openthe switch d and close the switch c by contacting with the contact |8I'of the switch disc 14, and thus open the mains circuit of the gearmotor C and close that of the gear motor D for the doctoring. After thespur wheel has performed half a revolution the secondary current flowsalong the following path: source ofcurrentv |09, feed wire IIO, springcontact |8I of spur wheel 3I, friction contacts |I3, ||4 and their wiresH5, II6, switch d, which is opened, return wire III, switch c, which isclosed, return wire I, source of current |09. By the opened switch d theswitch of the relay i series connected with the motor AC is opened andthis motor C stopped. By the closed switch c the switch -of a relay hseries-connected with the motor D is closed and the doctor motor Dswitched on. As the doctor motor D rotates the mains circuit is asfollows: feed wire |06, switch c, wire ||1, relay h, which is keptclosed over the return wire |01, wire H8,

doctor motor D, return wire' |01. After suiiicient doctoring with thedoctor device II has beenl done the doctor motor D is stopped again bythe star switch 8|. The secondary circuit then flows along the followingpath: source of current |09, feed wire l| I0, contact Aspring 83, starcontact 82, wire I|9, switch c, which is opened, wire III, switch bwhich is closed, returned through source of current |09. By the openingof the switch c the relay h is also opened and the doctor motor Dstopped. By the closing of switch b the relay i is closed 'and the gearmotor C restarted. The motor C receives its current from the mains Mthrough feed wire |06, switch b, Wire II2, relay i which is held closedover'the return wire |01, wire |30, motor C, return wire |01, mains M.The motor C now running again rotates the spur wheel 3| through half arevolution with the result that the stencils 6 are raised. In thisraised position the motor C is again switched oil by the switch disc 14and at the same time the magnets 61, 69 of the catch L receive mainscurrent over the switch f and the clutch E for the quick forwardmovement of the printing support A2 through the switch a. The secondarycurrent then flows from the source of current |09 through wire I| 0,spring contact |3I, friction contacts ||4, |20, I2I, their wires I|6,|22, |23, switch ,f which is-clo'sed, wire ||I, switch b which isopened,

wire I I I, switch a, which is closed, back through wire III, .source ofcurrent |09. The current now ows from thevmains through the feed wire|06, switch f and switch a, wire |24, magnets 61, 69 of the catch L,return wire |01 and wire |25, clutch `E for the quick feed movements ofthe printing supportV 2, back throughv wire |01 to the mains M. Theclutch L under current clamps tightly on the printing support 2 by whichit is movedforward with theaid of the clutch VE. The oncoming catchLknocks over the abutment 91 arranged in the path of the printingsupport 2 and by means of its contacts 98, 99 successively closes twospring contacts Il ll, |02 the first of which |0| breaks the circuit ofthe clutch E for the high-speed, whereas the second contact |02 closes'a moment later the circuit of the clutch F for the creeping speed. Theopening and closing oi' the circuits `of both clutches E and F iseffected again over the switches e and y d. The 'secondary circuitextends as follows:

source of current |09, Wire ||0, path contact 98, contact spring I0|,its wire I 2B, switch a which is opened and a moment late source ofcurrent |09, wire IIO, path contact 99, contact spring |02, its wire|27, switch c which is closed, back through wire source of current |09.From the mains wire M the current now flows through the feed wire |06,switch e, wire |28, clutch F for the creeping speed, return wire |07.The printing support 2 now brings the catch L at creeping speed up tothe second abutment lever 59 which is also knocked over and thusoscillates the hand 60 of the iine adjusting device K, which movement isconsiderably magniiled so that the end of this hand brushes over thecontact 6|, whereby the switches d, e, f in the secondary circuit H0,are simultaneously aotuated, so that the mains circuit M of the creepingmotion clutch F and of the magnets 61, 69 of the catch L are opened andthat' of the gear motor C is closed for the purpose of lowering thestencils 6. The sequence of operations then commences afresh. -Byswitching off the-motor A by the press button switch 91 the machine isbrought to a standstill. Clutches may be employed instead of theauxiliary motors C andl D which clutches may also be controlled byswitches similar to the switches a-^f, so that all movements of themachine can be controlled by a single driving motor.

I claim:

1. An electric stencil printing machine comprising in combination anintermittently travelling laterally unshiftable and unstretchableprinting support, stencils arranged above said support, a device forheating said support, heated printing and washing devices, acontinuously rotating motor, va controlled gearbetween said motor andsaid support, two clutches one for rapid speed and the other forcreeping speed, a catch adapted to'clamp on said support during theforward motion of said support to successively disengage the clutch forrapid speed, engage and disengage the clutch for creeping speed, a iineadjusting device for indicating the register position and actuated bysaid catch and adapted to release said catch for theY return movement,an auxiliary motor controlled by said device, a toothed wheel adapted tobe rotated through half a revolution by said auxiliary motor, a switchdisc connected to said toothed wheel adapted to lower said stencils, asecond auxiliary motor controlled by said disc, a doctor mechanism abovesaid support moved to and fro by said second auxiliary motor, saidsecond auxiliary motor adapted to again switch on said auxiliary motorto raise said stencils and engage the clutch for rapid speed and clampsaid clutch on said printing support.

2. In a stencil printing machine as speciiied in claim 1, the iineadjusting device comprising an indicator indicating on a larger scaleand havf ing two arms of diierent lengths, the short arm aisaoov magnetadapted to hold said pin in raised inoperative position, said magnetrendered currentless with that oi the catch when the catch reaches itsend position.

4. In a stencil printing machine as specified in' claim 1, means forreturning the catch from its end position into its initial position,said means comprising a screw spindle driven bythe ,main driving motor,a pin in said catch adapted to engage in the thread of said screwspindle, and a magnet adapted to hold said pin in raised inoperativeposition, said magnet rendered currentless with that of the catch whenthe catch reaches its end position, said spindle having an annulargroove in which the pinv and consequently the catch are held in theirinitial positions until their magnets are again excited.

5. A stencil printing machine as specified in claim 1, in which thedoctoring device. comprises a motor-actuated pull aggregate, at leastbolt, a pull rope fixed at both ends to said carriage, a plurality ofpulleys continually guiding said rope on a tortuous path, and a doctorholder attachedto several sections of said rope moving in the samedirection.

6. A stencil printing machine as specified in claim '1, in` which thedoctoring device comprises guide bars, a carriage shiitable on saidguide bars, vertical pins resiliently mounted on said carriage. a doctorholder vertically shiftable on said pins, cam races slidable at the sideof said carriage, rollers supporting said doctor holder on said camraces, doctors mounted on said holders, abutments at the ends of saidguide bars, cam noses at their ends, and a nose ascending towards themiddle, said noses adapted to cooperate with said abutments to transportsaid doctor holder into its extreme positions and in each of thesepositions to raise said holder and bring the doctors behind the heap ofink on the stencils.

7. A stencil printing machine as specified in claim l, in which thedoctoring device comprises a motor-actuated pull aggregate at least onepin in said pull aggregate, an an'chor bolt in said pull laggregate, acarriage mounted on said bolt, a pull rope i'lxed at both ends to saidcarriage, a .plurality of pulleys continually guiding said rope on atortuous path, and a doctor holder attached to several sections of saidrope moving in the same direction, contacts on the switch disccooperating with the cams on said pull aggregate to close the circuit ofthe third motor and Astop this motor after said disc has performedrotary movement determined by the position oi' said contacts and by thenumber of said cams, to determine the number of to and i'ro movements ofthe doctor holder.

8. A stencil printing machine as specified in claim 1, in which themachine comprises a printing table, a pasting apparatus, a pressurecylinder, a washing apparatus, and a'drying apparatus all arranged inthe path of travel of the endless printing support, and a heating plantadapted to feed heating `medium through said printing table, pastingapparatus, pressure cylinder, washing apparatus and drying apparatus.

9. In -a stencil printing machine as speciiied in clai 1, a pastingapparatus comprising a 5 multipartite ribbed body adapted to applystripes of paste on to the printing support, a paste i'eed roll, saidribbed body and said paste roll frictionvally driven by said printingsupport, a squeegee roller bearing on said paste feed roll to determine10 the amount of paste fed, and a pressurecylinder adapted to press thepaper web on to the pasted printing support, the ribs on said -ribbedbody being oi such width and so spaced that the pasted stripes remainseparate even after pressure has 15 been excited by said pressurecylinder.` v

10. In a stencil printing machine as specified v in claim 1. saidwashing apparatus i'or the printing support, comprising a container forhot water, brushes rotating partly submerged in the water 20 in saidcontainer, laterally reciprocatable strippers mounted above saidbrushes, and counter pressure rollers cooperating with said brushes andstrippers to b rush and scrape the printing support.

u 11. In a stencil printing machine as speciiied in claim 1, means forxing the stencils, compris-- ing iront and rear bars, front and rearriders adapted to iix said stencils to said bars, abutment bolts on saidstencilst he front riders adapted to engage behind the abutment bolts onsaid sten- 5 cils. the front. bars serving as abutments for the printingtable, and hand operated screws on the front riders adapted to presstightly against said front bars, and laterally adjustable abutment boltson the rear riders adapted t0 laterally se- 10 cure the rear ends oi'the stencils.

12.' A stencil printing machine as specified in claim 1, in which thedriving motors, the controlled gear, the toothed wheel, the doctormechaniam and the catch are controlled by switches 15 in a secondarycircuit.

13. In a stencil printing machine as specified in claim 1, means forraising and lowering the stencils comprising stencil holding bars and arod system connecting said bars with the toothed 20 wheel, the switchdisc being only operative when the stencil holding bars are in theirextreme positions to switch oit said auxiliary motor and switch on thethird motor.

JOSEF KESSEL. 26

